MDEV-14511 Use fewer transactions for updating InnoDB persistent stat…

…istics dict_stats_exec_sql(): Expect the caller to always provide a transaction. Remove some redundant assertions. The caller must hold dict_sys->mutex, but holding dict_operation_lock is only necessary for accessing data dictionary tables, which we are not accessing. dict_stats_save_index_stat(): Acquire dict_sys->mutex for invoking dict_stats_exec_sql(). dict_stats_save(), dict_stats_update_for_index(), dict_stats_update(), dict_stats_drop_index(), dict_stats_delete_from_table_stats(), dict_stats_delete_from_index_stats(), dict_stats_drop_table(), dict_stats_rename_in_table_stats(), dict_stats_rename_in_index_stats(), dict_stats_rename_table(): Use a single caller-provided transaction that is started and committed or rolled back by the caller. dict_stats_process_entry_from_recalc_pool(): Let the caller provide a transaction object. ha_innobase::open(): Pass a transaction to dict_stats_init(). ha_innobase::create(), ha_innobase::discard_or_import_tablespace(): Pass a transaction to dict_stats_update(). ha_innobase::rename_table(): Pass a transaction to dict_stats_rename_table(). We do not use the same transaction as the one that updated the data dictionary tables, because we already released the dict_operation_lock. (FIXME: there is a race condition; a lock wait on SYS_* tables could occur in another DDL transaction until the data dictionary transaction is committed.) ha_innobase::info_low(): Pass a transaction to dict_stats_update() when calculating persistent statistics. alter_stats_norebuild(), alter_stats_rebuild(): Update the persistent statistics as well. In this way, a single transaction will be used for updating the statistics of a whole table, even for partitioned tables. ha_innobase::commit_inplace_alter_table(): Drop statistics for all partitions when adding or dropping virtual columns, so that the statistics will be recalculated on the next handler::open(). This is a refactored version of Oracle Bug#22469660 fix. RecLock::add_to_waitq(), lock_table_enqueue_waiting(): Do not allow a lock wait to occur for updating statistics in a data dictionary transaction, such as DROP TABLE. Instead, return the previously unused error code DB_QUE_THR_SUSPENDED. row_merge_lock_table(), row_mysql_lock_table(): Remove dead code for handling DB_QUE_THR_SUSPENDED. row_drop_table_for_mysql(), row_truncate_table_for_mysql(): Drop the statistics as part of the data dictionary transaction. After TRUNCATE TABLE, the statistics will be recalculated on subsequent ha_innobase::open(), similar to how the logic after the above-mentioned Oracle Bug#22469660 fix in ha_innobase::commit_inplace_alter_table() works. btr_defragment_thread(): Use a single transaction object for updating defragmentation statistics. dict_stats_save_defrag_stats(), dict_stats_save_defrag_stats(), dict_stats_process_entry_from_defrag_pool(), dict_defrag_process_entries_from_defrag_pool(), dict_stats_save_defrag_summary(), dict_stats_save_defrag_stats(): Add a parameter for the transaction. dict_stats_empty_table(): Make public. This will be called by row_truncate_table_for_mysql() after dropping persistent statistics, to clear the memory-based statistics as well.
MariaDB · Dec 6, 2017 · 7dc6066 · 7dc6066
1 parent 2c1e4d4
commit 7dc6066
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diff --git a/mysql-test/suite/innodb/r/innodb_stats_debug.result b/mysql-test/suite/innodb/r/innodb_stats_debug.result
@@ -0,0 +1,12 @@
+call mtr.add_suppression("InnoDB: Cannot save (table|index) statistics for table `test`\\.`t1`.*: Persistent statistics do not exist");
+CREATE TABLE t1 (a INT, KEY(a)) ENGINE=INNODB STATS_PERSISTENT=1;
+SET @save_debug= @@SESSION.debug_dbug;
+SET debug_dbug= '+d,stats_index_error';
+ANALYZE TABLE t1;
+Table	Op	Msg_type	Msg_text
+test.t1	analyze	status	Operation failed
+SET debug_dbug= @save_debug;
+ANALYZE TABLE t1;
+Table	Op	Msg_type	Msg_text
+test.t1	analyze	status	OK
+DROP TABLE t1;
diff --git a/mysql-test/suite/innodb/t/innodb_stats_debug.test b/mysql-test/suite/innodb/t/innodb_stats_debug.test
@@ -0,0 +1,13 @@
+--source include/have_innodb.inc
+--source include/have_debug.inc
+
+call mtr.add_suppression("InnoDB: Cannot save (table|index) statistics for table `test`\\.`t1`.*: Persistent statistics do not exist");
+
+CREATE TABLE t1 (a INT, KEY(a)) ENGINE=INNODB STATS_PERSISTENT=1;
+SET @save_debug= @@SESSION.debug_dbug;
+SET debug_dbug= '+d,stats_index_error';
+ANALYZE TABLE t1;
+SET debug_dbug= @save_debug;
+ANALYZE TABLE t1;
+
+DROP TABLE t1;
diff --git a/mysql-test/suite/innodb/t/innodb_stats_drop_locked.test b/mysql-test/suite/innodb/t/innodb_stats_drop_locked.test
@@ -57,5 +57,5 @@ SELECT table_name FROM mysql.innodb_index_stats
 WHERE table_name='innodb_stats_drop_locked';
 
 --disable_query_log
-call mtr.add_suppression("Unable to delete statistics for table test.innodb_stats_drop_locked: Lock wait timeout. They can be deleted later using DELETE FROM mysql.innodb_index_stats WHERE database_name");
+call mtr.add_suppression("Unable to delete statistics for table test\\.innodb_stats_drop_locked: Lock wait");
 --enable_query_log
diff --git a/storage/innobase/btr/btr0defragment.cc b/storage/innobase/btr/btr0defragment.cc
@@ -751,6 +751,8 @@ DECLARE_THREAD(btr_defragment_thread)(void*)
 	buf_block_t*	first_block;
 	buf_block_t*	last_block;
 
+	trx_t* trx = trx_allocate_for_background();
+
 	while (srv_shutdown_state == SRV_SHUTDOWN_NONE) {
 		ut_ad(btr_defragment_thread_active);
 
@@ -826,31 +828,33 @@ DECLARE_THREAD(btr_defragment_thread)(void*)
 			/* Update the last_processed time of this index. */
 			item->last_processed = now;
 		} else {
-			dberr_t err = DB_SUCCESS;
 			mtr_commit(&mtr);
 			/* Reaching the end of the index. */
 			dict_stats_empty_defrag_stats(index);
-			err = dict_stats_save_defrag_stats(index);
+			++trx->will_lock;
+			dberr_t err = dict_stats_save_defrag_stats(index, trx);
+			if (err == DB_SUCCESS) {
+				err = dict_stats_save_defrag_summary(
+					index, trx);
+			}
+
 			if (err != DB_SUCCESS) {
+				trx_rollback_to_savepoint(trx, NULL);
 				ib::error() << "Saving defragmentation stats for table "
-					    << index->table->name.m_name
-					    << " index " << index->name()
-					    << " failed with error " << err;
-			} else {
-				err = dict_stats_save_defrag_summary(index);
-
-				if (err != DB_SUCCESS) {
-					ib::error() << "Saving defragmentation summary for table "
-					    << index->table->name.m_name
-					    << " index " << index->name()
-					    << " failed with error " << err;
-				}
+					    << index->table->name
+					    << " index " << index->name
+					    << " failed with error "
+					    << ut_strerr(err);
+			} else if (trx->state != TRX_STATE_NOT_STARTED) {
+				trx_commit_for_mysql(trx);
 			}
 
 			btr_defragment_remove_item(item);
 		}
 	}
 
+	trx_free_for_background(trx);
+
 	btr_defragment_thread_active = false;
 	os_thread_exit();
 	OS_THREAD_DUMMY_RETURN;

diff --git a/storage/innobase/dict/dict0defrag_bg.cc b/storage/innobase/dict/dict0defrag_bg.cc
@@ -1,6 +1,6 @@
 /*****************************************************************************
 
-Copyright (c) 2016, MariaDB Corporation. All Rights Reserved.
+Copyright (c) 2016, 2017, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -29,6 +29,7 @@ Created 25/08/2016 Jan Lindström
 #include "dict0defrag_bg.h"
 #include "row0mysql.h"
 #include "srv0start.h"
+#include "trx0roll.h"
 #include "ut0new.h"
 
 #include <vector>
@@ -201,12 +202,12 @@ dict_stats_defrag_pool_del(
 	mutex_exit(&defrag_pool_mutex);
 }
 
-/*****************************************************************//**
-Get the first index that has been added for updating persistent defrag
-stats and eventually save its stats. */
+/** Get the first index that has been added for updating persistent defrag
+stats and eventually save its stats.
+@param[in,out]	trx	transaction that will be started and committed  */
 static
 void
-dict_stats_process_entry_from_defrag_pool()
+dict_stats_process_entry_from_defrag_pool(trx_t* trx)
 {
 	table_id_t	table_id;
 	index_id_t	index_id;
@@ -240,63 +241,58 @@ dict_stats_process_entry_from_defrag_pool()
 		return;
 	}
 
-	dict_stats_save_defrag_stats(index);
+	++trx->will_lock;
+	dberr_t err = dict_stats_save_defrag_stats(index, trx);
+
+	if (err != DB_SUCCESS) {
+		trx_rollback_to_savepoint(trx, NULL);
+		ib::error() << "Saving defragmentation status for table "
+			    << index->table->name
+			    << " index " << index->name
+			    << " failed " << err;
+	} else if (trx->state != TRX_STATE_NOT_STARTED) {
+		trx_commit_for_mysql(trx);
+	}
+
 	dict_table_close(table, FALSE, FALSE);
 }
 
-/*****************************************************************//**
-Get the first index that has been added for updating persistent defrag
-stats and eventually save its stats. */
+/** Process indexes that have been scheduled for defragmenting.
+@param[in,out]	trx	transaction that will be started and committed  */
 void
-dict_defrag_process_entries_from_defrag_pool()
-/*==========================================*/
+dict_defrag_process_entries_from_defrag_pool(trx_t* trx)
 {
 	while (defrag_pool->size() && !dict_stats_start_shutdown) {
-		dict_stats_process_entry_from_defrag_pool();
+		dict_stats_process_entry_from_defrag_pool(trx);
 	}
 }
 
-/*********************************************************************//**
-Save defragmentation result.
+/** Save defragmentation result.
+@param[in]	index	index that was defragmented
+@param[in,out]	trx	transaction
 @return DB_SUCCESS or error code */
 dberr_t
-dict_stats_save_defrag_summary(
-/*============================*/
-	dict_index_t*	index)	/*!< in: index */
+dict_stats_save_defrag_summary(dict_index_t* index, trx_t* trx)
 {
-	dberr_t	ret=DB_SUCCESS;
-	lint	now = (lint) ut_time();
-
 	if (dict_index_is_ibuf(index)) {
 		return DB_SUCCESS;
 	}
 
-	rw_lock_x_lock(dict_operation_lock);
-	mutex_enter(&dict_sys->mutex);
-
-	ret = dict_stats_save_index_stat(index, now, "n_pages_freed",
-					 index->stat_defrag_n_pages_freed,
-					 NULL,
-					 "Number of pages freed during"
-					 " last defragmentation run.",
-					 NULL);
-
-	mutex_exit(&dict_sys->mutex);
-	rw_lock_x_unlock(dict_operation_lock);
-
-	return (ret);
+	return dict_stats_save_index_stat(index, ut_time(), "n_pages_freed",
+					  index->stat_defrag_n_pages_freed,
+					  NULL,
+					  "Number of pages freed during"
+					  " last defragmentation run.",
+					  trx);
 }
 
-/*********************************************************************//**
-Save defragmentation stats for a given index.
+/** Save defragmentation stats for a given index.
+@param[in]	index	index that is being defragmented
+@param[in,out]	trx	transaction
 @return DB_SUCCESS or error code */
 dberr_t
-dict_stats_save_defrag_stats(
-/*============================*/
-	dict_index_t*	index)	/*!< in: index */
+dict_stats_save_defrag_stats(dict_index_t* index, trx_t* trx)
 {
-	dberr_t	ret;
-
 	if (dict_index_is_ibuf(index)) {
 		return DB_SUCCESS;
 	}
@@ -305,7 +301,6 @@ dict_stats_save_defrag_stats(
 		return dict_stats_report_error(index->table, true);
 	}
 
-	lint	now = (lint) ut_time();
 	mtr_t	mtr;
 	ulint	n_leaf_pages;
 	ulint	n_leaf_reserved;
@@ -322,40 +317,33 @@ dict_stats_save_defrag_stats(
 		return DB_SUCCESS;
 	}
 
-	rw_lock_x_lock(dict_operation_lock);
-
-	mutex_enter(&dict_sys->mutex);
-	ret = dict_stats_save_index_stat(index, now, "n_page_split",
-					 index->stat_defrag_n_page_split,
-					 NULL,
-					 "Number of new page splits on leaves"
-					 " since last defragmentation.",
-					 NULL);
-	if (ret != DB_SUCCESS) {
-		goto end;
-	}
-
-	ret = dict_stats_save_index_stat(
-		index, now, "n_leaf_pages_defrag",
-		n_leaf_pages,
+	lint now = ut_time();
+	dberr_t err = dict_stats_save_index_stat(
+		index, now, "n_page_split",
+		index->stat_defrag_n_page_split,
 		NULL,
-		"Number of leaf pages when this stat is saved to disk",
-		NULL);
-	if (ret != DB_SUCCESS) {
-		goto end;
+		"Number of new page splits on leaves"
+		" since last defragmentation.",
+		trx);
+	if (err == DB_SUCCESS) {
+		err = dict_stats_save_index_stat(
+			index, now, "n_leaf_pages_defrag",
+			n_leaf_pages,
+			NULL,
+			"Number of leaf pages when this stat is saved to disk",
+			trx);
 	}
 
-	ret = dict_stats_save_index_stat(
-		index, now, "n_leaf_pages_reserved",
-		n_leaf_reserved,
-		NULL,
-		"Number of pages reserved for this index leaves when this stat "
-		"is saved to disk",
-		NULL);
-
-end:
-	mutex_exit(&dict_sys->mutex);
-	rw_lock_x_unlock(dict_operation_lock);
+	if (err == DB_SUCCESS) {
+		err = dict_stats_save_index_stat(
+			index, now, "n_leaf_pages_reserved",
+			n_leaf_reserved,
+			NULL,
+			"Number of pages reserved for this "
+			"index leaves when this stat "
+			"is saved to disk",
+			trx);
+	}
 
-	return (ret);
+	return err;
 }